As if Justin Bieber's supernova status were not already bewildering enough for anyone past the age of majority, the baby-faced Canadian singer, who looks even younger than his 16 years, has just announced his first memoir, First Step 2 Forever: My Story, via HarperCollins. He may not be the youngest celebrity to write an autobiography – Drew Barrymore and Charlotte Church were both 15 when they published, respectively, 1990's Little Girl Lost and 2001's Voice of an Angel: My Life (So Far) – but he is the only one who can also boast a forthcoming 3D biopic (apparently helmed by the Oscar-winning director of An Inconvenient Truth, no less) about his prodigious rise.

Explaining this explosion in Bieberology, the singer gave potential readers some idea of the kind of pulse-pounding prose they can expect: "My fans have played such a large part in all of this and they help me live my dreams every day . . . This is just another way to say thank you to my fans."

He has a lot to thank them for. A long, long time ago, in early 2007, Bieber's mother posted on YouTube a clip of her 12-year-old son performing Ne-Yo's So Sick at a singing contest in Stratford, Ontario. The clip's phenomenal popularity won him a deal with Island Records and his 2009 album My World gave rise to commercial superlatives, making him the youngest solo male US chart-topper since Stevie Wonder in 1963, the first artist ever to score seven hit singles from a debut, and the star of the most-viewed YouTube clip to date (Baby stands at over 270 million views).

Bieber is a distinctly modern celebrity, discovered and nurtured by fans on the internet. He was a Twitter trending topic for months until Twitter changed the rules in May to reflect spiking popularity rather than consistent mentions. When Lily Allen made the mistake of mocking Bieber on the social network, she was quickly savaged by some of his 4 million followers. (Judging by his Twitter feed, First Step 2 Forever will be generous with the exclamation marks!!)

The Bieberholics' fervour is not in doubt. The singer's manager was charged with reckless endangerment and criminal nuisance after fans mobbed a Long Island mall while waiting to see their idol. The anti-Bieber camp is active too, hacking his YouTube clips, spreading death rumours and hijacking an online poll to choose a "bonus country" for his world tour (half a million wags voted for North Korea). But there's nothing his detractors can do to halt Bieber's march, nor the inevitable blockbuster sales of First Step 2 Forever. The question is not if there will be a sequel, but how soon he can get away with one.